The present invention relates to a receiving device for use in magnetic resonance imaging (MRI) and spectroscopy systems to enhance the imaging performance and spectroscopy sensitivity of such instruments when evaluating anatomical regions small in size relative to the body, and deep within the body, but proximate a location where an insertable pickup probe could be used. Specifically, the present invention relates to an intracavity pickup probe designed to image the prostate region by rectal introduction, to image the cervix region by vaginal introduction, or the like.
In the field of MRI systems, also commonly known as NMR imaging systems, external pickup probes are typically used for receiving radio frequency signals from the region of interest. For optimum performance however, the pickup probe should be insertable for intracavity use and which includes a radio frequency receiving coil, to be positioned as close to the region of interest as possible. In addition, the insertable pickup probe should also have a sensitive volume equaling the desired field of view of the region of interest. This allows optimization of the "filling factor" and "coupling coefficient" for the specific MRI system, thereby improving signal to noise ratio in MR imaging.
Furthermore, for optimum sensitivity, the receving coil should have an unloaded coil quality factor (Q) which is as great as possible and should be adjusted to resonate at the exact Larmour frequency of the scanner of the MRI system. It also sometimes is desired that the insertable, intracavity pickup probe be disposable, and hence the cost of the probe should be minimized as much as possible. At the same time, it is important that in reducing the cost of the probe, the ability to impedance match and tune the receiving coil to the scanner of the MRI system not be compromised. Therefore, there is a need to provide a disposable pickup probe at minimal cost for use in a MRI system which is capable of automatically or manually tuning and impedance matching the receiving coil to the scanner of the MRI system.